Metatarsophalangeal joint preparation and metatarsal realignment for fusion

ABSTRACT

A method of preparing a metatarsophalangeal joint for fusion may involve surgically accessing the metatarsophalangeal joint and separating the metatarsal from the opposed proximal phalanx at the joint. The technique may involve preparing an end of the metatarsal and preparing an end of the opposed proximal phalanx for fusion. With or without the aid of a bone positioner, the metatarsal may be moved in one or more planes, such as the frontal and transverse planes. The proximal phalanx may also be moved in one or more planes, for example relative to the moved metatarsal. Subsequently, a bone fixation device can be applied across or through the metatarsophalangeal joint separating the metatarsal from the opposed proximal phalanx.

RELATED MATTERS

This application claims the benefit of U.S. Provisional PatentApplication No. 62/968,244, filed Jan. 31, 2020, the entire contents ofwhich are incorporated herein by reference.

TECHNICAL FIELD

This disclosure relates to devices and techniques formetatarsophalangeal joint preparation and metatarsal realignment.

BACKGROUND

The human foot includes the five toes (which are also known as the“phalanges”) and their connecting long bones (or “metatarsals”). Thejoint between a metatarsal and a phalange is called themetatarsophalangeal (“MTP”) joint. Several small bones together comprisea phalanx or toe. Four of the five toes have three phalanx bonesrespectively connected by two joints. The big toe (or “hallux”) has twophalanx bones distal and proximal with a joint in between called theinterphalangeal joint. The big toe articulates with the head of thefirst metatarsal at the first metatarsophalangeal joint (the “MTP”joint) and there are two tiny, round bones called sesamoids on theplantar side of the metatarsal head. The phalanges are connected to themetatarsals at the ball of the foot. The two sesamoid bones are locatedunderneath the first metatarsal bone and assist in flexion of the bigtoe at the first MTP joint.

Hallux rigidus is a degenerative disease of the firstmetatarsophalangeal joint. It is the most common form of arthritis inthe foot, reportedly affecting 1 in 40 people over the age of 50. Thefirst MTP joint plays an important functional role during the gait cycleas it carries a significant amount of an individual's body weight witheach step. Osteophyte formation and degeneration of the cartilage occursdorsally in early stages of the disease and progresses to involve theentire first MTP joint. Consequently, individuals with Hallux rigidusexperience joint pain and decreased range of motion in the sagittalplane. This leads to altered gait mechanics and significant reduction inactivity and quality of life for patients.

SUMMARY

In general, this disclosure is directed to devices and techniques forpreparing the metatarsophalangeal (“MTP”) joint for fusion andrealigning the metatarsal and phalanx separated by the joint. In someimplementations, a clinician surgically accesses the MTP joint andseparates the metatarsal from the opposed phalanx for subsequent bonepreparation and realignment. The clinician may make a longitudinalincision, e.g., just medial to the extensor hallucis longus tendon. Withthe MTP joint exposed, the clinician may separate the end face of themetatarsal from the end face of the opposed phalanx to provide workingspace. The clinician may subsequently prepare the end face of themetatarsal and the end face of the opposed phalanx for fusion. Examplepreparation steps may include reaming, cutting, rongeuring, curetting,burring, fenstrating and/or other similar techniques for exposingsubchondral bone and/or establishing bleeding bone faces to promotefusion following rejoining of the metatarsal and phalanx.

Either before or after preparation of one or both end faces, themetatarsal is realigned within one or more planes in three-dimensionalspace. In one example, the clinician engages a bone positioner with themetatarsal and a bone other than the metatarsal. The bone positioner canthen be actuated to move the metatarsal in one or more planes forrealignment. The use of the bone positioner can provide an instrumentedapproach to metatarsal realignment that allows for repeatable,consistent clinical outcomes patient-to-patient andclinician-to-clinician. In other examples, however, the clinician mayrealign the metatarsal manually without the aid of an instrumented bonepositioner bridging between the metatarsal and another anchoring bone.The clinician may realign the metatarsal in one or more planes at atime, e.g., including the frontal plane.

Independent of the specific technique the clinician uses to realign themetatarsal, the clinician may also realign the proximal phalanx relativeto the metatarsal. As one realignment, the clinician may adjust theorientation of the phalanx in the sagittal plane to help set a desiredamount of dorsiflexion. As another example realignment, the clinicianmay rotate the phalanx within the frontal plane to help provideanatomically accurate positioning of the plantar side of the phalanx inthe frontal plane.

To help guide accurate realignment and visualization of the proximalphalanx, the clinician may provisionally fixate the phalanx to anadjacent bone during and/or after realignment. For example, theclinician may insert a pin (e.g., a Kirschner wire, which is alsoreferred to as a K wire) through the distal end of the phalanges andadvance the pin proximally toward the metatarsal.

In the case of the first metatarsal, for instance, the clinician caninsert the pin through the distal phalanx followed by the proximalphalanx and then lodge the distal portion of the pin in the firstmetatarsal. The pin can project distally out of the distal phalanx,providing a visible axis of rotation for realigning the proximal phalanxin the frontal plane. When so implemented, the clinician may first setthe orientation of the phalanx in the sagittal and/or transverse planeand then pin the phalanx to the metatarsal in that orientation. Theclinician can then set the orientation of the phalanx in the frontalplane, e.g., by rotating the phalanx in the frontal plane about the pin.Once the orientation of the phalanx is set in the frontal plane,provisional and/or permanent fixation can be used to hold the movedposition of the phalanx relative to the metatarsal for subsequentfusion.

According to some example implementations of the devices and techniquesdescribed herein, the metatarsal and phalanx separated by the MTP jointcan be independently realigned relative to each other. For example, theposition of the metatarsal in three-dimensional space may first beadjusted to a desired moved position and provisionally held in thatmoved position during subsequent realignment of the phalanx. Theposition of the phalanx can then be adjusted to a desired moved positionin three-dimensional space (e.g., relative to the metatarsal that hasalready been realigned). With the metatarsal and proximal phalanx eachindependently realigned relative to each other, one or more fixationdevices can be applied across and/or through the MTP joint to promotesubsequent fusion of the bones. For example, one or more plates, screws,pins, and/or the like can be applied to permanently fixate themetatarsal to the phalanx and promote fusion of the bones at the MTPjoint.

Through the stepwise adjustment of the orientation of the metatarsal andopposed phalanx, the position of each bone can be adjusted from ananatomically misaligned position toward a position of anatomicalalignment.

In one example, a method is described that includes preparing ametatarsophalangeal joint for fusion. The method includes surgicallyaccessing a metatarsophalangeal joint separating a metatarsal from anopposed proximal phalanx and preparing an end of the metatarsal andpreparing an end of the opposed proximal phalanx. The method alsoincludes moving the metatarsal in at least two planes to establish amoved position of the metatarsal and applying at least one bone fixationdevice across or through the metatarsophalangeal joint separating ametatarsal from an opposed proximal phalanx.

In another example, a method of preparing a metatarsophalangeal jointfor fusion is described. The method includes surgically accessing ametatarsophalangeal joint separating a metatarsal from an opposedproximal phalanx, preparing an end of the metatarsal and preparing anend of the opposed proximal phalanx, and engaging a bone positioningguide with the metatarsal and a bone other than the metatarsal. Themethod also includes actuating the bone positioning guide and therebymoving the metatarsal in at least one plane to establish a movedposition of the metatarsal and applying at least one bone fixationdevice across or through the metatarsophalangeal joint separating ametatarsal from an opposed proximal phalanx.

The details of one or more examples are set forth in the accompanyingdrawings and the description below. Other features, objects, andadvantages will be apparent from the description and drawings, and fromthe claims.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B are front views of a foot showing a normal firstmetatarsal position and an example frontal plane rotational misalignmentposition, respectively.

FIGS. 2A and 2B are top views of a foot showing a normal firstmetatarsal position and an example transverse plane misalignmentposition, respectively.

FIGS. 3A and 3B are side views of a foot showing a normal firstmetatarsal position and an example sagittal plane misalignment position,respectively.

FIG. 4 is a flow diagram illustrating an example technique for preparingthe MTP joint for fusion and realigning the metatarsal and proximalphalanx separated by the joint.

FIG. 5 is a perspective view of a foot showing example surgical accessto the MTP joint.

FIG. 6 is a side view of a first metatarsal and sesamoid complex showingthe position of the sesamoid bones when in proper anatomical alignment.

FIG. 7 is a side view of the first metatarsal and sesamoid complex fromFIG. 6 showing an example anatomical misalignment of the sesamoid bones.

FIG. 8 is a perspective image of a foot illustrating an examplepreparation step performed on first metatarsal.

FIG. 9 is a perspective illustration of an example bone positioningdevice that can be used to move a metatarsal.

FIG. 10 is a perspective view of a foot showing the bone positioningdevice of FIG. 9 attached to the foot.

FIG. 11 is a perspective view of a foot showing an example pin insertedinto the hallux of the foot and into the first metatarsal.

FIG. 12 is a fluoroscopic image of the foot of FIG. 11 taken in thedorsal to plantar direction.

FIG. 13 is a perspective view of a foot showing a compression pininserted through the proximal phalanx and into the first metatarsalalong with an example bone plate.

FIG. 14 is a perspective view of a foot showing example bi-planar boneplates.

FIGS. 15A-15D are illustrations of example surgical steps that may beperformed to engage a compressor with a metatarsal and opposed proximalphalanx to facilitate compression.

FIGS. 16 and 17 are pre- and post-operative fluoroscopic images of afoot showing example bone realignment according to the techniques of thepresent disclosure.

DETAILED DESCRIPTION

In general, the present disclosure is directed to devices and techniquesfor preparing the metatarsophalangeal (“MTP”) joint for fusion andrealigning the metatarsal and phalanx separated by the joint. While atechnique according to the disclosure can be performed on any MTP jointwhere a metatarsal is joined to an opposing proximal phalanx, in someimplementations, the technique is performed on the first MTP joint wherethe first metatarsal joins the first proximal phalanx. During theprocedure, a metatarsal may be separated from an opposing proximalphalanx at the MTP joint and both the metatarsal and opposing phalanxrepositioned within one or more planes. After suitably repositioning themetatarsal and opposed proximal phalanx, the bone portions may be fixedto each using one or more fixation devices crossing the MTP joint. Theend faces of the metatarsal and opposed proximal phalanx can be preparedprior to fixation, e.g., to promote realignment and/or subsequent fusionof the bones to each other.

Preparation and fusion of a metatarsal and phalanx may be performedaccording to the disclosure for a variety of clinical reasons andindications. Preparation and fusion of a metatarsal and proximal phalanxat the MTP joint may be performed to treat Hallux rigidus, Halluxvalgus, and/or other bone and/or joint conditions.

Hallux rigidus is characterized as a degenerative arthritis of the MTPjoint, particularly the first MTP joint. The cause of Hallux rigidus isoften unclear. While arthritis can be caused by traumatic or iatrogenicinjuries that directly cause damage to the articular cartilage of theMTP joint, most commonly the aetiology of Hallux rigidus is idiopathic.Patients may have family history and/or bilateral involvement leading toHallux rigidus. As Hallux rigidus progresses, the normal coupling of thecenter of rotation of the proximal phalanx and metatarsal head may bedisrupted, leading to eccentric gliding of proximal phalanx on themetatarsal head. Osteophytes may form preferentially on the dorsalsurface. Further, while a normal first MTP motion may have approximately75° of dorsiflexion and 35° of plantarflexion, patients with Halluxrigidus may typically exhibit a decreased range of motion, such asdorsiflexion less than 60°, such as less than 40°, less than 30°, oreven less than 20°.

Hallux valgus, also referred to as hallux abducto valgus, is a complexprogressive condition that is characterized by lateral deviation(valgus, abduction) of the hallux and medial deviation of the firstmetatarsophalangeal joint. Hallux valgus typically results in aprogressive increase in the hallux abductus angle, the angle between thelong axes of the first metatarsal and proximal phalanx in the transverseplane. An increase in the Hallux abductus angle may tend to laterallydisplace the plantar aponeurosis and tendons of the intrinsic andextrinsic muscles that cross over the first metatarsophalangeal jointfrom the metatarsal to the hallux. Consequently, the sesamoid bones mayalso be displaced, e.g., laterally relative to the firstmetatarsophalangeal joint, resulting in subluxation of the jointsbetween the sesamoid bones and the head of the first metatarsal. Thiscan increase the pressure between the medial sesamoid and the crista ofthe first metatarsal head.

While the techniques and devices are described herein particularly inconnection with the first metatarsal and first proximal phalanx of thefoot, the techniques and devices may be used on other adjacent bonesseparated by a joint in the hand or foot. For example, the techniquesand devices may be performed on a different metatarsal (e.g., second,third, fourth, or fifth metatarsal) and its opposed proximal phalanx.

To further understand example techniques of the disclosure, the anatomyof the foot will first be described with respect to FIGS. 1-3 along withexample misalignments that may occur and be corrected according to thepresent disclosure. As noted, a bone misalignment and/or MTP joint painmay be caused by hallux valgus (bunion), Hallux rigidus, a naturalgrowth deformity, and/or other condition. The condition may present witha misalignment of one or more bones in the foot. Alternatively, thecondition may present with evidence of arthritis at the MTP jointwithout visible misalignment of the bone forming the joint.

FIGS. 1A and 1B are front views of foot 200 showing a normal firstmetatarsal position and an example frontal plane rotational misalignmentposition, respectively. FIGS. 2A and 2B are top views of foot 200showing a normal first metatarsal position and an example transverseplane misalignment position, respectively. FIGS. 3A and 3B are sideviews of foot 200 showing a normal first metatarsal position and anexample sagittal plane misalignment position, respectively. While FIGS.1B, 2B, and 3B show each respective planar misalignment in isolation, inpractice, a metatarsal may be misaligned in any two of the three planesor even all three planes. Accordingly, it should be appreciated that thedepiction of a single plane misalignment in each of FIGS. 1B, 2B, and 3Bis for purposes of illustration and a metatarsal may be misaligned inmultiple planes that is desirably corrected. Further, a bone conditiontreated according to the disclosure may not present any of the examplemisalignments described with respect to FIGS. 1B, 2B, and 3B, and itshould be appreciated that the disclosure is not limited in thisrespect.

With reference to FIGS. 1A and 2A, foot 200 is composed of multiplebones including a first metatarsal 210, a second metatarsal 212, a thirdmetatarsal 214, a fourth metatarsal 216, and a fifth metatarsal 218. Themetatarsals are connected distally to phalanges 220 and, moreparticularly, each to a respective proximal phalanx. In particular, thefirst metatarsal 210 is connected distally to first proximal phalanx250, the second metatarsal 212 is connected distally to second proximalphalanx 252, the third metatarsal 214 is connected distally to thirdproximal phalanx 254, the fourth metatarsal 216 is connected distally tofourth proximal phalanx 256, and the fifth metatarsal 218 is connecteddistally to fifth proximal phalanx 258. The joint 232 between ametatarsal and a corresponding opposed proximal phalanx is referred toas a metatarsophalangeal (“MTP”) joint. The first MTP joint is labeledas joint 232 in FIG. 2A, although second, third, fourth, and fifth MTPjoints are also illustrated in series adjacent to the first MTP joint.

The first metatarsal 210 is connected proximally to a medial cuneiform222, while the second metatarsal 212 is connected proximally to anintermediate cuneiform 224 and the third metatarsal is connectedproximally to lateral cuneiform 226. The fourth and fifth metatarsals216, 218 are connected proximally to the cuboid bone 228. The joint 230between a metatarsal and respective cuneiform (e.g., first metatarsal210 and medial cuneiform 222) is referred to as the tarsometatarsal(“TMT”) joint. The angle 234 between adjacent metatarsals (e.g., firstmetatarsal 210 and second metatarsal 212) is referred to as theintermetatarsal angle (“IMA”).

As noted, FIG. 1A is a frontal plane view of foot 200 showing a typicalposition for first metatarsal 210. The frontal plane, which is alsoknown as the coronal plane, is generally considered any vertical planethat divides the body into anterior and posterior sections. On foot 200,the frontal plane is a plane that extends vertically and isperpendicular to an axis extending proximally to distally along thelength of the foot. FIG. 1A shows first metatarsal 210 in a typicalrotational position in the frontal plane. FIG. 1B shows first metatarsal210 with a frontal plane rotational deformity characterized by arotational angle 236 relative to ground, as indicated by line 238.

FIG. 2A is a top view of foot 200 showing a typical position of firstmetatarsal 210 in the transverse plane. The transverse plane, which isalso known as the horizontal plane, axial plane, or transaxial plane, isconsidered any plane that divides the body into superior and inferiorparts. On foot 200, the transverse plane is a plane that extendshorizontally and is perpendicular to an axis extending dorsally toplantarly (top to bottom) across the foot. FIG. 2A shows firstmetatarsal 210 with a typical IMA 234 in the transverse plane. FIG. 2Bshows first metatarsal 210 with a transverse plane rotational deformitycharacterized by a greater IMA caused by the distal end of firstmetatarsal 210 being pivoted medially relative to the second metatarsal212.

FIG. 3A is a side view of foot 200 showing a typical position of firstmetatarsal 210 in the sagittal plane. The sagittal plane is a planeparallel to the sagittal suture which divides the body into right andleft halves. On foot 200, the sagittal plane is a plane that extendsvertically and intersects an axis extending proximally to distally alongthe length of the foot. FIG. 3A shows first metatarsal 210 with atypical rotational position in the sagittal plane. FIG. 3B shows firstmetatarsal 210 with a sagittal plane rotational deformity characterizedby a rotational angle 240 relative to ground, as indicated by line 238.

Bone positioning techniques and instruments can be useful to correct amisalignment of one or more bones, such as the metatarsal and opposedproximal phalanx, and/or promote fusion of the metatarsal and proximalphalanx across the MTP joint. In some applications, the techniqueinvolves releasing the MTP joint and preparing the end faces of themetatarsal and proximal phalanx for realignment relative to each otherand/or fusion. The metatarsal undergoing the procedure may be moved inat least two planes, such as all three planes, to provide a movedposition for fusing with the proximal phalanx. The proximal phalanxundergoing the procedure may also be moved in at least one plane, suchas two or all three planes, relative to the metatarsal and/or anadjacent proximal phalanx. Once the metatarsal and proximal phalanx areappropriately repositioned, the metatarsal and proximal phalanx can befixated to hold and maintain their relative positions to each other,e.g., and to promote fusion between the bones.

FIG. 4 is a flow diagram illustrating an example technique for preparingthe MTP joint for fusion and realigning the metatarsal and proximalphalanx separated by the joint. The technique will be described withrespect to first metatarsal 210 and first proximal phalanx 250, whichare joined at the first MTP joint 232, although can be performed onother bones, as discussed above. For purposes of discussion, thetechnique of FIG. 4 will be discussed with respect to different exampleimages of a procedure illustrated in FIGS. 5-16 .

FIG. 5 is a perspective view of a foot 200 showing example surgicalaccess to the MTP joint. With reference to FIGS. 4 and 5 , the exampletechnique involves surgically accessing metatarsophalangeal joint 232separating first metatarsal 210 from its opposed proximal phalanx 250(300). To surgically access the joint, the patient may be placed in asupine position on the operating room table and general anesthesia orMonitored Anesthesia Care (MAC) administered. Hemostasis can be obtainedby applying thigh tourniquet or mid-calf tourniquet. An incision 400(FIG. 5 ) can be made on a dorsal side of the foot 200, such as adorsal-medial side of the foot. For example, incision 400 may be madejust medial to the extensor hallucis longus tendon centered over thefirst MTP joint 232. In some applications, a full thicknesssub-periosteal dissection is carried out exposing the first MTP joint232.

With the MTP joint 232 exposed, first metatarsal 210 may be separatedfrom first proximal phalanx 250 at the joint. For example, firstproximal phalanx 250 may be pushed plantarly, resulting in the end faceof the first proximal phalanx separating from the end face of firstmetatarsal 210 to provide access to both end faces for subsequentoperation. If needed, a soft tissue release performed at MTP joint 232to help separate and release the metatarsal from the phalanx. Whenpresent, exuberant bony exostosis can be removed from the head (e.g., edface) of the first metatarsal 210 and the base (e.g., end face) of theproximal phalanx 250.

In some examples of the technique of FIG. 4 , the sesamoid complex isrepositioned under the first metatarsal 210 (302). FIG. 6 is a side viewof a first metatarsal and sesamoid complex showing the position of thesesamoid bones when in proper anatomical alignment. With reference toFIG. 6 , the sesamoid bones 402, 404 are two bones positioned under thefirst metatarsal 210 when the bones and metatarsal are in properanatomical realignment. The medial and lateral aspects of the plantarsurface of the head of the first metatarsal 210 normally form shallowparallel grooves on either side of the central sagittal ridge called thecrista 406. The medial and lateral sesamoid bones articulate with themedial and lateral grooves, respectively. The sesamoid bones slideforward in their respective grooves during extension (windlass action)and backward during flexion (reverse windlass action) of the first MTPjoint 232 when in proper alignment.

In the case of a misalignment, however, the sesamoid bones 402, 404 maybe displaced (e.g., laterally) relative to the first MPT joint 232. FIG.7 is a side view of the first metatarsal and sesamoid complex from FIG.6 showing an example anatomical misalignment of the sesamoid bones.Displacement of the sesamoid bones 402, 404 may cause increased pressurebetween the medial sesamoid 402 and the crista 406 of the firstmetatarsal head 210 and decreased pressure between the lateral sesamoid404 and the first metatarsal head.

In the technique of FIG. 4 , the medial sesamoid bone 402 and thelateral sesamoid bone 404 may be repositioned on opposite sides of thesagittal plane 408. For example, the sesamoid bones 402, 404 may bepositioned on opposite sides of the crista 406 within the respectiveparallel grooves formed by the head of the first metatarsal 210. Toreposition the sesamoid bones, an instrument may be used tosubstantially fully release the capsular tissue at the MTP joint and forcomplete release of the sesamoids from the metatarsal. For example, aMcGlamery elevator instrument may be used inserted (e.g., plantarly ofthe metatarsal) to release capsular tissue and to release the sesamoids,although a number of other instruments can be used instead of thisparticular device. The sesamoid bones 402, 404 may naturally realignupon being released from the first metatarsal 210, although manualmanipulation or rotation (e.g., with or without the aid of a furtherinstrument) may be used to assist realignment of the sesamoid bones.

Before or after the sesamoid bones are optionally repositioned in thetechnique of FIG. 4 (302), the end face of the first metatarsal 210and/or the end face of the proximal phalanx 250 may be prepared (304,306). Bone preparation can be useful, for instance, to facilitatecontact between leading edges of metatarsal 210 and proximal phalanx250. Preparation of the end faces may allow the two bones to berealigned relative to each other and/or to prepare the end faces topromote fusion between the end faces.

To prepare the end face of the first metatarsal 210 and/or the end faceof the first proximal phalanx 250, a tissue removing instrument can beapplied to the end face. Example tissue removing instruments that can beused include, but are not limited to, a saw, a rotary bur, a rongeur, areamer, an osteotome, and the like. The tissue removing instrument canbe applied to the end face of the bone being prepared to removecartilage and/or bone. For example, the tissue removing instrument maybe applied to the end face to remove cartilage (e.g., all cartilage)down to subchondral bone. Additionally or alternatively, the tissueremoving instrument may be applied to cut, fenestrate, morselize, and/orotherwise reshape the end face of the bone and/or form a bleeding boneface to promote fusion. In instances where a cutting operation isperformed to remove an end portion of first metatarsal 210 and/or firstproximal phalanx 250, the cutting may be performed freehand or with theaid of cutting guide having a guide surface positionable over theportion of bone to be cut. When using a cut guide, a cutting instrumentcan be inserted against the guide surface (e.g., between a slot definebetween two guide surfaces) to guide the cutting instrument for boneremoval.

FIG. 8 is a perspective image of foot 200 illustrating an examplepreparation step performed on first metatarsal 210 (304). In theillustrated example, a guide pin 410 is inserted to project distally outof the end face of first metatarsal 210. A generally concave reamer 412(e.g., a cone reamer) is advanced axially down the guide pin 412 androtated using a rotary instrument 416 (e.g., drill). Reamer 412 (orother instrument, if a different surgical instrument is used) may denudethe end face of the first metatarsal 210 of remaining cartilage down tothe subchondral bone plate. In some examples, the end face of the firstmetatarsal 210 may be fenestrated in addition to or in lieu of one ormore other end preparation steps, such as reaming the face with reamer412.

The proximal phalanx 250 may be prepared using the same preparationtechnique or techniques performed on first metatarsal 210 or using adifferent preparation technique or techniques (306). In instances wherethe end face of the first metatarsal is prepared using a generallyconically-shaped reamer 412, the end face of the first proximal phalanx250 may be prepared using a corresponding generally convex reamer (e.g.,a cup reamer). A guide pin may be inserted into the end face of thefirst proximal phalanx 250 and the convex reamer advanced down the guidepin and rotated using a rotary instrument. The reamer (or otherinstrument, if a different surgical instrument is used) may denude theend face of the proximal phalanx 250 of remaining cartilage down to thesubchondral bone plate. In some examples, the end face of the proximalphalanx 250 may be fenestrated in addition to or in lieu of one or moreother end preparation steps, such as reaming the face with the reamer.

In general, the specific order of the surgical steps performed in thetechnique of FIG. 4 may be varied without departing from the scopedisclosure, and the example order illustrated in FIG. 4 it is merely forpurposes of illustration. For example, the end face of the firstmetatarsal 210 may be prepared before or after the end face of theproximal phalanx 250 is prepared. Further, although FIG. 4 illustratesthe end faces of the two bones as being prepared before moving either ofthe bones for realignment, one or both bones may be moved to a realignedposition, as will be described below, before preparing an end face ofone or both bones.

The technique of FIG. 4 involves moving the first metatarsal (e.g.,relative to an adjacent metatarsal, such as a second metatarsal 212,and/or the first proximal phalanx 250) to establish a moved position ofthe metatarsal (308). In different examples, movement of the firstmetatarsal may be performed freehand (e.g., without the aid of a bonepositioning device) and/or using instrumentation (e.g., a bonepositioning device) to help facilitate repeatable repositioningoutcomes.

When a bone positioning device is used, the bone positioning device maybe any instrument that engages with the metatarsal being repositioned(e.g., first metatarsal 210) and a bone other than the metatarsal beingrepositioned. For example, the bone positioning device may engage withthe metatarsal 210 on one side and another bone that acts as an anchorfor the bone positioning device during actuation and correspondingmovement of the metatarsal. The other bone used to anchor the bonepositioning device may be another metatarsal (e.g., second metatarsal212 or yet other metatarsal), a cuneiform such as medial cuneiform 222,or yet other anchoring bone. The bone positioning device may engage withthe metatarsal being moved and the other bone through frictional contactwithout being fixedly coupled to the bone. Additionally oralternatively, a pin, screw, and/or other fixation element may be usedto secure the bone positioning device to one or both bones.

In general, a bone positioning device may apply a force to a bone thatcauses the bone to move in at least one plane, such as the transverseplane and/or the frontal plane. In some examples, the force applied bythe bone positioning device moves the metatarsal to which the force isapplied in multiple planes, such as at least two planes or all threeplanes. For example, the bone positioning device may cause the firstmetatarsal 210 to be moved in the transverse plane to close theintermetatarsal angle and may also cause the metatarsal to rotate in thefrontal plane.

FIG. 9 is a perspective illustration of an example bone positioningdevice 10 that can be used to move first metatarsal 210. Additionaldetails on bone positioning device 10 can be found in U.S. Pat. No.9,936,994, titled “BONE POSITIONING GUIDE,” and issued Apr. 10, 2018,the entire contents of which are incorporated herein by reference.

In the example of FIG. 9 , a bone positioning device 10 (which may alsobe referred to as a bone positioning guide) includes a main body member20, a shaft 30, a bone engagement member 40 connected to the shaft, anda tip 50 is connected to the main body member. In general, the main bodymember 20 can be sized and shaped to clear anatomy or otherinstrumentation (e.g., pins and guides) while positioned on a patient.As illustrated, the main body member 20 includes a generally C-shapedconfiguration with a first end 60 and a second end 70. In someembodiments, the main body is sized and configured to engage ametatarsal to be moved with bone engagement member 40 and anothermetatarsal that functions as an anchoring bone with tip 50. Althoughbone positioning device 10 is illustrated as being formed of twocomponents, main body member 20 and shaft 30, the guide can befabricated from more components (e.g., three, four, or more) that arejoined together to form the guide.

Shaft 30 can be movably connected to the main body member 20 proximateits first end 60. In some embodiments, the shaft 30 includes threads 80that engage with the main body member 20 such that rotation of the shafttranslates the shaft with respect to the main body member. In otherembodiments, the shaft can slide within the main body member and can besecured thereto at a desired location with a set screw. In yet otherembodiments, the shaft can be moved with respect to the main body by aratchet mechanism, e.g., with or without a third device or by theclinician's hand pressure.

To move the ends of bone positioning device 10 relative to each other tomove a bone engaged therewith, bone positioning device 10 can alsoinclude an actuator (e.g., a knob or a handle) 120 to actuate themechanism. In the embodiment shown, the actuator can be useful forallowing a user to rotate the shaft with respect to the main body member20. As shown, the actuator, shaft, and bone engagement member mayinclude a cannulation to allow the placement of a fixation wire (e.g.,K-wire) through these components and into contact with or through a boneengaged with the bone engagement member. For example, the fixation wirecan be placed into the bone engaged with bone engagement member 40 tofix the position of the bone engagement member with respect to the bone.In another example, the fixation wire can be placed through the bone incontact with the bone engagement member and into an adjacent bone tomaintain a bone position of the bone in contact with the bone engagementmember and the adjacent bone.

While FIG. 9 illustrates one example configuration of a bone positioningdevice, the disclosure is not limited to the use of a bone positioningdevice with such an illustrated configuration. As one alternativeexample, instead of being configured to engage a metatarsal to be movedwith bone engagement member 40 and another metatarsal with tip 50, thebone positioning device may be configured to extend from a metatarsal tobe moved to a bone other than a metatarsal, such as a cuneiform to whichthe bone positioning device is anchored. As another example, a bonepositioning device may utilize a tenaculum or tong structure to move oneend engaged with the metatarsal relative to another anchoring bone. As afurther example, a band, suture, and/or other interconnecting member maybe attached to the metatarsal and a bone other than the metatarsal andthen used to apply and/or translate a force to move the metatarsal.

In yet further examples, the clinician may use an instrument to apply aforce to move the metatarsal without having the instrumentsimultaneously contact the metatarsal and a bone other than themetatarsal, e.g., in addition to or in lieu of using an bone positioningdevice that contacts both the metatarsal being moved and a bone otherthan the metatarsal. For example, the clinician may insert a pin intothe metatarsal and manually manipulate the pin to control movement ofthe metatarsal. As another example, the clinician may insert one pininto a metatarsal and another pin into a bone other than the metatarsal(e.g., one into first metatarsal 210 and one into second metatarsal212). The clinician may then squeeze the two pins together.

Independent of the configuration of the bone positioning device used (ininstances where a bone positioning device is used), the bone positioningdevice may be configured to move the metatarsal being realigned in atleast one plane (e.g., relative to the opposed proximal phalanx) and/oran adjacent metatarsal, such as at least two planes, or all threeplanes. The at least one plane can be the transverse plane, the frontalplane, and/or the sagittal plane. In some embodiments, actuation of thebone positioning device moves the metatarsal in at least the transverseplane to close the intermetatarsal angle (“IMA”), e.g., between firstmetatarsal 210 and second metatarsal 212. Actuation of the bonepositioning device may reduce the IMA to an angle less than 12 degrees,such as less than 10 degrees, less than 8 degrees, less than 6 degrees,or less than 4 degrees.

In addition to or in lieu of moving the metatarsal in the transverseplane, actuation of the bone positioning device may realign themetatarsal in the frontal plane. A normal first metatarsal will bepositioned such that its crista prominence is generally perpendicular tothe ground and/or its sesamoid bones are generally parallel to theground and positioned under the metatarsal. This position can be definedas a metatarsal rotation of 0 degrees. In a misaligned first metatarsal,the metatarsal may be axially rotated between about 4 degrees to about30 degrees or more. In some embodiments, the metatarsal is moved in thefrontal plane to reducing the metatarsal rotation from about 4 degreesor more to less than 4 degrees (e.g., to about 0 to 2 degrees) byrotating the metatarsal.

In some implementations, such as when utilizing a bone positioningdevice 10 as illustrated in FIG. 9 , actuation of the bone positioningdevice may simultaneously move the metatarsal in two planes to establisha moved position with respect to those planes. For example, actuatingbone positioning device 10 may cause first metatarsal 210 to move in thetransverse plane to close the IMA and in the frontal plane to move thecrista prominence toward a 0 degree rotation angle.

When actuating the bone positioning device, the metatarsal may or maynot also move in the sagittal plane (e.g., plantarly). For instance, insome implementations, actuating the bone positioning device causes themetatarsal to move in the transverse plane to close the IMA and thefrontal plane to reduce the degree of rotation without any significantmovement in the sagittal plane (e.g., such that there is less than 5degrees of sagittal plane movement). This can maintain the sagittalplane declination of the first metatarsal while the position of themetatarsal is corrected in two other planes.

In some such example, the clinician may or may not perform a separatestep to adjust the position of the metatarsal in the sagittal plane. Forexample, either before or after adjusting the position of the metatarsalin the transverse plane and/or frontal plane, the clinician may adjustthe position of the metatarsal in the sagittal plane to help set adesired amount of dorsiflexion. For example, after moving firstmetatarsal 210 in the transverse plane and the frontal plane using bonepositioning device 10, the clinician may manually grasp the metatarsal(e.g., by grasping the metatarsal directly, grasping a pin connected tothe metatarsal, and/or with the use of a tong-type instrument) and movethe first metatarsal in the sagittal plane. Bone positioning device 10may continue to engage the metatarsal while the metatarsal is beingmoved in the sagittal plane, e.g., the help hold the moved position ofthe metatarsal in the frontal and/or transverse planes.

In some examples, the clinician moves first metatarsal 210 in thesagittal plane to help a declination angle (plantarflexion) for thefirst metatarsal that is substantially the same as the declination angleexhibited by an adjacent metatarsal (e.g., second metatarsal). Thedeclination angle of the first metatarsal relative to the secondmetatarsal may be observed by taking a lateral X-ray image of foot 200.In some examples, the clinician moves first metatarsal 210 in thesagittal plane to set a declination angle relative to ground that iswithin approximately 5 degrees (plus or minus) of the declination angleof the second metatarsal, such as less than 3 degrees (plus or minus)different than the declination angle of the second metatarsal, or lessthan 2 degrees (plus or minus) different than the declination angle ofthe second metatarsal. In addition to or in lieu of moving the firstmetatarsal 210 relative to a declination angle of the second metatarsal212, the clinician may move the metatarsal in the sagittal plane toestablish a declination angle relative to ground, such as an angleranging from 10 to 35 degrees with respect to ground, or from 20 to 25degrees with respect to ground.

FIG. 10 is a perspective view of foot 200 showing bone positioningdevice 10 attached to the foot. In the example, the bone engagementmember of bone positioning device 10 is placed in contact with firstmetatarsal 210, such as on the medial ridge of the first metatarsal. Thetip 50 of bone positioning device 10 is placed through a stab incisionon the lateral cortex of the second metatarsal 212. Actuation of bonepositioning device 10 can cause a first ray deformity to be reduced onin the transverse and frontal planes.

If desired, a clinician may utilize a fulcrum between the metatarsalbeing moved and an adjacent metatarsal, e.g., to prevent compression ofthe metatarsals together during actuation of the bone positioningdevice. When used, the fulcrum may be inserted in the intermetatarsalspace, e.g., between the distal head of the first metatarsal 210 and theadjacent second metatarsal 212. Additionally or alternatively, thefulcrum may be inserted between the proximal base of the metatarsal andthe proximal base of an adjacent metatarsal (e.g., between the proximalbase of the first and second metatarsals 210, 212), such as be making astab incision at the base between the two metatarsals and inserting thefulcrum through the incision. Details on example fulcrum structures thatmay be used can be found in U.S. Pat. No. 10,342,590, issued Jul. 9,2019 and titled “TARSAL-METATARSAL PROCEDURE UTILZING FULCRUM,” theentire contents of which are incorporated herein by reference.

While the foregoing description has described the metatarsal as beingmoved in at least one plane with the aid of a bone positioning device,in other examples, the clinician may move the metatarsal by hand withoutthe aid of a bone positioning device providing controlled movement ofthe metatarsal relative to another bone that the bone positioning deviceis also engaged with. In these alternative examples, the clinician maygenerally move the metatarsal in at least one plane, such as at leasttwo planes (e.g., any two of the frontal, transverse, and sagittalplanes), or all three planes. The clinician can move the metatarsal inone plane at a time, resulting in multiple different movements toachieve the multi-planar movement. Additionally or alternatively, theclinician may perform a single repositioning of the metatarsal inmultiple planes. The clinician may move the metatarsal to any of thepositions and/or angular ranges discussed above with respect to movementachieved when also using a bone positioning device.

Independent of whether the clinician utilizes a bone positioning deviceor moves the metatarsal without the aid of bone positioning device, theclinician may or may not insert two parallel reference pins to helpvisualize the bone movement. For example, prior to moving the metatarsal210, the clinician may insert a first pin into the metatarsal and asecond, parallel pin into the first proximal phalanx 250. The two pinsmay project out of the respective bones. As the bones are moved inthree-dimensional space and/or relative to each other, the orientationof the two pins may shift out of parallel alignment. This may provide avisual guide to the clinician on the extent of relative movement betweenthe bones.

In the example technique of FIG. 4 , the first proximal phalanx 250opposing the metatarsal 210 may be moved in at least one plane inaddition to or in lieu of moving the metatarsal (310). For example,either before or after moving the first metatarsal 210 in at least oneplane, the proximal phalanx 250 may be moved in at least one plane(e.g., any one of the frontal, transverse, and sagittal planes), such asat least two planes. For example, after moving the first metatarsal 210in one, two, or three planes, the clinician may move the proximalphalanx in the sagittal plane and frontal plane relative to the movedmetatarsal.

To help facilitate positioning of the proximal phalanx 250 relative tothe first metatarsal 210, the clinician may provisionally fixate theposition of the moved metatarsal. As one example, the clinician mayinsert a pin (e.g., a guide wire or K-wire) through the moved metatarsaland into another bone, such as an adjacent metatarsal (e.g., secondmetatarsal 212). When using bone positioning device 10, the pin can beinserted through the cannula in the actuator, through the firstmetatarsal, and into the second metatarsal. Alternatively, the bonepositioning device used to apply a force to move the metatarsal mayremain engaged with the bone (e.g., with actuator optionally locked),thereby functioning to hold the metatarsal in the moved position forsubsequent realignment of the proximal phalanx 250. In still otherexamples, the moved metatarsal may not be provisionally held with a pinand/or instrumentation while adjusting the alignment of the proximalphalanx 250.

In one implementation, the clinician moves the proximal phalanx 250 andsets the position of the proximal phalanx using a pin extendinggenerally parallel to the long axis of the proximal phalanx. Forexample, after moving the first metatarsal 210 to a desired position,the clinician may insert a pin (e.g., guide wire, K-wire) from thedistal end of the hallux toward the moved metatarsal. The clinician canadvance the pin in a distal to proximal direction through the distalphalanx 260 followed by the proximal phalanx 250 and into the end faceof the first metatarsal 210. Prior to advancing the pin out of theproximal end face of the proximal phalanx 250 and into the distal endface of the first metatarsal 210, the clinician may move the proximalphalanx 250 (and attached distal phalanx 260) to a desired sagittalplane position and/or transverse plane position and/or frontal planeposition. With the proximal phalanx 250 moved to a desired position inthe sagittal plane, the clinician may advance the pin out of theproximal end face of the proximal phalanx 250 and into the distal endface of the first metatarsal 210, thereby provisionally fixating theproximal phalanx 250 to the first metatarsal 210 and holding the setsagittal plane position for the proximal phalanx. Additional details onexample pin insertion and placement techniques may be found in U.S. Pat.No. 9,622,805, titled “BONE POSITIONING AND PREPARING GUIDE SYSTEMS ANDMETHODS,” issued Apr. 18, 2017, the entire contents of which areincorporated herein by reference.

FIG. 11 is a perspective view of foot 200 showing an example pin 420inserted into the hallux of the foot and into the first metatarsal,e.g., to provisionally fixate the proximal phalanx relative to themetatarsal at a desired angular position in the sagittal plane. Pin 420is shown projecting out the distal end of the hallux for visualizationby the clinician. FIG. 12 is an X-ray of the foot 200 of FIG. 11 takenin the dorsal to plantar direction. The X-ray shows how pin 420 isinserted through distal phalanx 260, proximal phalanx 250, and intofirst metatarsal 210.

A variety of alternative provisional fixation instruments and/ortechniques can be used in addition to or in lieu of a pin insertedproximally through the proximal phalanx 250 and into the firstmetatarsal 210. For example, a pin may be insert through the firstmetatarsal 210 into the proximal phalanx (e.g., from the dorsal side ofthe first metatarsal and advanced distally and plantarly across the MTPjoint). As another example, a pin may be inserted into the proximal endof the proximal phalanx 250 to a depth sufficient to provide a smallsection of pin protruding out of the proximal end of the proximalphalanx. The pin may be positioned with distal end of the pin protrudingout another side of the proximal phalanx. In either case, the proximalphalanx 250 can then be moved to a desired position with respect to themetatarsal 210. The pin can then be driven back through the proximalphalanx 250, e.g., by engaging the distal end of the pin with a drivermechanism, and into another bone, such as the opposed metatarsal 210.

In some examples, the clinician moves proximal phalanx 250 in thesagittal plane to help set a dorsiflexion angle measured relative toground ranging from 0 degrees to 20 degrees, such as from approximately5 degrees to approximately 10 degrees of dorsiflexion relative to theground. The clinician may place the foot (or at least the metatarsal andhallux portion of the foot) on a planar surface, such a planar surfaceof a board or block. The clinician may then visualize and set thedesired angle of proximal phalanx 250 in the sagittal plane relative tothe planar surface. For example, the clinician may position the weightbearing surface of the foot in contact with the planar surface and viewthe position of the hallux interphalangeal joint, e.g., as pin 420 isbeing inserted and/or the position of the proximal phalanx is beingadjusted in the sagittal plane. The clinician may set the plantar headof the proximal phalanx 250 at an angle of inclination relative wherethe weight bearing surface contacts the planar surface, e.g., within anyof the foregoing angular ranges discussed above. In some examples, theclinician sets the plantar head of the proximal phalanx 250 to bepositioned a distance less than 4 mm off of the planar surface contactedby the weight bearing surface of the foot, such as less than 3 mm, or adistance ranging from approximately 1 mm to approximately 2 mm.

In addition to or in lieu of positioning proximal phalanx 250 in thesagittal plane, the clinician be move the proximal phalanx in thetransverse plane. The clinician may move the proximal phalanx to besubstantially parallel to an adjacent proximal phalanx, e.g., such as bymoving the first proximal phalanx 250 to be parallel to the secondproximal phalanx 252.

With proximal phalanx 250 optionally provisionally fixated to firstmetatarsal 210 using pin 420, the clinician may move the proximalphalanx in the front plane to set a desired frontal plane position ofthe proximal phalanx. For example, the clinician can utilize pin 420 asa frontal plane axis of rotation and rotate proximal phalanx 250 aboutthe pin to a desired frontal plane rotation position. The clinician mayuse the hallux and/or toenail as a reference for neutral or slightsupination alignment of the hallux. The clinician may de-rotate proximalphalanx 250 until there is substantially no frontal plane rotation ofthe hallux.

With the proximal phalanx 250 moved to a desired position, the clinicianmay utilize intra-operative fluoroscopy to confirm the position of thefirst metatarsal 210 and/or proximal phalanx 250. For example, theclinician may generate fluoroscopic images in both theanterior-posterior view and lateral view to visualize the position ofthe bones in three-dimensional space. If needed, correctiverepositioning of the metatarsal and/or proximal phalanx can beperformed. Otherwise, if the clinician is satisfied with the positioningof the bones, the clinician may permanently fixate the MTP joint forfusion with the metatarsal and proximal phalanx in their relative movedpositions.

In some examples, the clinician may compress the prepared end face ofthe proximal phalanx against the prepared end face of the metatarsal tofacilitate fusion together prior to applying one or more permeantfixation devices. For example, the clinician use pin 420 to compress theproximal phalanx 250 to the first metatarsal 210, compressing the MTPjoint. Additionally or alternatively, the clinician may insert acompression pin (e.g., a screw, a partially threaded olive wire, aK-wire, etc.) to compress across the MTP joint, e.g., by inserting thecompression member from the dorsal-medial base of the proximal phalanx250 across the first MTP joint 232 into the proximal-lateral firstmetatarsal shaft 210 for compression. When pin 420 is already insertedinto the bones, the second pin may stabilize the frontal-planecorrection of the phalanx. FIG. 13 is a perspective view of foot 200showing a compression pin 418 inserted through the proximal phalanx andinto the first metatarsal along with an example bone plate 422 beingapplied across the MTP joint.

To compress the prepared end of proximal phalanx 250 against theprepared end of first metatarsal 210 for fixation and fusion, acompressor instrument may optionally be used. FIGS. 15A-15D areillustrations of example surgical steps that may be performed to engagea compressor with a metatarsal and opposed proximal phalanx tofacilitate compression. Some or all of the example steps of FIGS.15A-15D up to compression may be performed before or after the end facesof the metatarsal and/or proximal phalanx are prepared and/or before orafter realignment of the metatarsal and proximal phalanx. Further, whilethe example steps of FIGS. 15A-15D are described in connection withengaging a compressor device, the steps of FIGS. 15A-15C mayadditionally or alternatively be utilized to insert generally parallelguide pins into the metatarsal and opposed proximal phalanx, e.g., tohelp visualize realignment of one or both bone portions.

With reference to FIG. 15A, an optional guide 430 may be positioned onthe first metatarsal 210 and/or opposed proximal phalanx 250. Guide 430can define one or more apertures through which one or more correspondingpins can be insert. For example, guide 430 may cross the MTP joint anddefine at least one aperture 432 positioned over the first metatarsal210 for receiving a pin and at least one aperture 434 positioned overthe proximal phalanx for receiving a pin. The apertures may be orientedrelative to each other to place the pins inserted therethrough at anydesired orientation with respect to each other, such as generallyparallel to each other and/or biased plantarly.

FIG. 15B illustrates a first pin 436 inserted through aperture 432 intofirst metatarsal 210 and a second pin 438 inserted through aperture 434into proximal phalanx 250. In this example, the first and second pins436, 438 extend dorsally and are generally parallel to each other. Withthe pin(s) positioned using optional guide 430, the guide may be removedas illustrated in FIG. 15C.

After suitably preparing and moving the first metatarsal 210 andproximal phalanx 250, the end face of the proximal phalanx can becompressed against the end face of the metatarsal. In some examples, anaxial wire or pin may be placed to extend proximally out of the end faceof the proximal phalanx. When used, the proximal phalanx may slide alongthe wire or pin during compression. In either case, a compressorinstrument 440 may be installed on the first pin 436 and the second pin438 and then engaged to compress the bones attached to the pinstogether, as illustrated in FIG. 15D. Additional details on compressorinstrumentation that may be used can be found in US Patent Publication2020/0015856, filed Jul. 11, 2019 and titled “COMPRESSOR-DISTRACTOR FORANGULARLY REALIGNING BONE PORTIONS,” the entire contents of which areincorporated herein by reference.

With reference to FIG. 4 , the example technique includes applying atleast one bone fixation device across or through the MTP jointseparating the metatarsal from the opposed proximal phalanx (312). Anyone or more bone fixation devices can be used including, but not limitedto, a compressing bone screw, a bone plate, a bone staple, an externalfixator, and/or an intramedullary implant. The bone fixation device maybe secured on one side to the metatarsal, bridge the MTP joint, and besecured on an opposite side to the proximal phalanx.

In one example, two bone plates may be placed across the MTP joint toprovide bi-planar plating. For example, a first bone plate may bepositioned on a dorsal-medial side of the metatarsal and proximalphalanx. A second bone plate may be positioned on a medial-plantar sideof the metatarsal and the proximal phalanx. Independent of the number orconfiguration of bone plates, the plates may be applied with theinsertion of bone screws. FIG. 14 is a perspective view of foot 200showing example bi-planar bone plates 422A, 422B applied across the MTPjoint to allow the metatarsal to fuse to the proximal phalanx duringsubsequent recovery.

FIGS. 16 and 17 are pre- and post-operative fluoroscopic images of afoot showing example bone realignment according to the techniques of thepresent disclosure.

Various examples have been described. These and other examples arewithin the scope of the following claims.

The invention claimed is:
 1. A method of preparing a metatarsophalangealjoint for fusion, the method comprising: surgically accessing ametatarsophalangeal joint separating a metatarsal from an opposedproximal phalanx; preparing an end of the metatarsal and preparing anend of the opposed proximal phalanx; moving the metatarsal in at leasttwo planes to establish a moved position of the metatarsal; applying atleast one bone fixation device at least one of across and through themetatarsophalangeal joint separating the metatarsal from the opposedproximal phalanx.
 2. The method of claim 1, wherein moving themetatarsal in at least two planes comprises moving the metatarsal inthree planes.
 3. The method of claim 2, wherein moving the metatarsalcomprises: moving the metatarsal in a frontal plane and a transverseplane, and after moving the metatarsal in the frontal plane and thetransverse plane, moving the metatarsal in a sagittal plane.
 4. Themethod of claim 1, wherein moving the metatarsal in at least two planescomprises reducing an angle between the metatarsal and an adjacentmetatarsal to less than 12 degrees.
 5. The method of claim 1, whereinmoving the metatarsal comprises moving the metatarsal after preparingthe end of the metatarsal and after preparing the end of the opposedphalanx.
 6. The method of claim 1, further comprising moving the opposedproximal phalanx relative to the metatarsal in at least a sagittalplane.
 7. The method of claim 6, further comprising moving the opposedproximal phalanx in a frontal plane.
 8. The method of claim 7, furthercomprising inserting a pin through the opposed proximal phalanx and intothe metatarsal, wherein moving the opposed proximal phalanx in thefrontal plane comprises rotating the proximal phalanx about the pin. 9.The method of claim 1, further comprising repositioning a medialsesamoid bone associated with the metatarsal and a lateral sesamoid boneassociated with the metatarsal on opposite sides of a sagittal plane.10. The method of claim 9, wherein repositioning the medial sesamoidbone and the lateral sesamoid bone comprises releasing the medialsesamoid bone and the lateral sesamoid bone with an instrument andrepositioning the medial sesamoid bone and the lateral sesamoid boneprior to moving the metatarsal in the at least two planes.
 11. Themethod of claim 1, further comprising engaging a bone positioning guidewith the metatarsal and a bone other than the metatarsal, wherein movingthe metatarsal in the at least two planes comprises actuating the bonepositioning guide and thereby moving the metatarsal in at least one ofthe two planes using the bone positioning guide.
 12. The method of claim11, wherein actuating the bone positioning guide comprises actuating thebone positioning guide and thereby moving the metatarsal in at least afrontal plane and a transverse plane.
 13. The method of claim 11,wherein engaging the bone positioning guide with the metatarsal and thebone other than the metatarsal comprises engaging the bone positioningguide with the metatarsal and another metatarsal.
 14. The method ofclaim 11, wherein the bone positioning guide comprises: a first endconfigured to engage the metatarsal and a second end configured toengage the bone other than the metatarsal, and a mechanism configured tomove the first end and the second end toward each other.
 15. The methodof claim 14, wherein the mechanism comprises at least one of a ratchetand a threaded shaft.
 16. The method of claim 1, wherein preparing theend of the metatarsal and preparing the end of the opposed proximalphalanx each comprises removing cartilage down to subchondral bone. 17.The method of claim 1, wherein: preparing the end of the metatarsalcomprises reaming the end of the metatarsal with a generallyconical-shaped reamer, and preparing the end of the opposed proximalphalanx comprises reaming the end of the opposed phalanx with agenerally cone-shaped reamer.
 18. The method of claim 1, furthercomprising, prior to applying the at least one bone fixation device,provisionally fixing the moved position of the metatarsal.
 19. Themethod of claim 18, wherein provisionally fixing the moved position ofthe metatarsal comprises inserting a pin into the metatarsal and a boneother than the metatarsal.
 20. The method of claim 19, wherein insertingthe pin into the metatarsal and the bone other than the metatarsalcomprises inserting the pin through the opposed proximal phalanx andinto the metatarsal.
 21. The method of claim 19, wherein inserting thepin into the metatarsal and the bone other than the metatarsal comprisesinserting the pin into the metatarsal and an adjacent metatarsal. 22.The method of claim 1, further comprising, prior to applying the atleast one bone fixation device, compressing the opposed proximal phalanxand the metatarsal together across the metatarsophalangeal joint. 23.The method of claim 1, wherein the at least one bone fixation devicecomprises at least one of a bone plate, a pin, a screw, and a staple.24. The method of claim 1, wherein the at least one bone fixation devicecomprises: a first plate, and at least one of a second plate and anintramedullary screw.
 25. A method of preparing a metatarsophalangealjoint for fusion, the method comprising: surgically accessing ametatarsophalangeal joint separating a metatarsal from an opposedproximal phalanx; preparing an end of the metatarsal and preparing anend of the opposed proximal phalanx; engaging a bone positioning guidewith the metatarsal and a bone other than the metatarsal; actuating thebone positioning guide and thereby moving the metatarsal in at least oneplane to establish a moved position of the metatarsal; applying at leastone bone fixation device at least one of across and through themetatarsophalangeal joint separating a metatarsal from an opposedproximal phalanx.